[development] SoC: Multi-site administration through rich XUL client

[Khalid B]

Anything that  requires repetitive operations to  many items.

More use cases:

- Rarranging the taxonomies by weight, and terms by weight
- Rarranging book pages by changing the weights
- Editing a lot of nodes to change something commone (e.g.
unpublish many nodes, remove sticky or promoted, ...etc.)
- Editing a lot of users to change something

You get the idea ...